She hunts aliens, she looks good in a trenchcoat, and she's the smartest sex symbol on TV ... but just who is the real Gillian Anderson? Anthony Noguera gets on her case

Dana Scully, the power-dressing strawberry blonde half of The X-file paranormal investigating FBI team, is the smartest woman on TV. She's a trained medical doctor, a dab hand with an autopsy scalpel and the finest student in her FBI class. And she's sexy too, in a sultry and appealingly natural way.

She's the calming influence on The X-files, reacting in a motherly fashion to Mulder's excitable and outlandish boy scout theories about man-eating worm beasts - raising just an eyebrow to register her utter disbelief. And although she has an infuriating habit of looking the wrong way whenever aliens land or ghosts appear, she's always prepared to blow away perps to save Mulder's arse when he gets in too deep. So far she's been chased by pre-historic bugs and flesh-eating cavewomen, experimented on by sinister government forces, been terrorised, shot at and kidnapped by aliens. And yet, despite everything, she manages to keep a cool head - offering a plausible solution when the implausible seems the only answer. And did you know that she's laughed only once, and that was in the pilot episode more than two years ago? So perhaps because she does it so infrequently, one of her smiles is worth a million of anyone else's.

Trying to think of an equivalent anywhere on TV is near on impossible; there are few enough heavyweight roles for women, even less that don't require some kind of contractual cleavage shots in every episode. Scully is renowned for her wits, not her tits. Even in such contemporary top-rated shows such as ER and Friends, the females are seen before they are heard. If real-life nurses looked like the ones in ER, no one would get saved -male doctors would just stand around all day gawping at them; and isn't it just fantastic that three leggy, sexy, drop-dead stunners (a blonde, a brunette and a dark-haired one) would end up sharing an apartment in Friends? And what of the almost obligatory 'caught in the shower' and 'waking up in the middle of the night to answer the door' scenes that most shows have to deal with? Nobody knows if Scully sleeps with her gun and we'll probably never see. But there are plenty of guys who'd like the chance to find out.

The X-files is unique in many ways, not least because it's the first TV show in living memory where the sexual tension between the leads is destined to go unconsummated. The tide of TV history is against them; tradition demands that Mulder and Scully get the shags in. But let's hope not; remember the tragic way that Moonlighting fell apart once David and Maddie got it together between the sheets, or how Cheers hit the skids once Sam and Diane did the dirty? By comparison, the relationship between Mulder and Scully remains simmering in its underpants.

Gillian Anderson's most ardent supporters, the Internet-based Gillian Anderson Testosterone Brigade call her "a role model for women and an object of complete, unabated affection for men". Furthermore, their motto runs "Gillian Anderson Is Intellectually Drop Dead Gorgeous". And they're not wrong. Yet all we know of Anderson is her portrayal of Scully. She has risen seemingly without a trace to star in the coolest cult hit on TV and yet there are no salacious tabloid rumours of a pre-X-files career as a Hollywood stripper, and no lurid ex-lover's tales of coke-fuelled orgies to spice up the gossip columns. The Gillian Anderson Testosterone Brigade would have us believe that Anderson and Scully are one and the same person. Let's find out, shall we . . .

Some facts about Gillian Anderson. She can juggle, "But not very well." She won a World Theatre Award for her role in Alan Ayckbourn's Absent Friends. The song that means the most to her right now is Hand in my Pocket by Alanis Morissette. The first boy she kissed was called Adam and her favourite actors are Robert De Niro, Jessica Lange, Meryl Streep and Gary Oldman. She's 27, married to a man called Klotz, has a daughter (Piper, 18 months old), her hair colour is naturally ash-blonde and she wears black jeans, white T-shirts and scuffed tan cowboy boots on her days off. And her favourite expletive is 'fuck me'.

"Hahhahaha! I was very into swearing as a child. I remember asking my mom what fuck meant, what fucking was, and I can't remember on my life what her response was. I remember hearing it in the playground when I was eight, off a kid who was 12. He fancied me and I fancied him but I was scared to death because his affection was like grown-up affection - he may have even done the fuck word. And I had no idea what it meant."

For nine months of the year, North Shore Studios in Vancouver (chosen for reasons of economy) is home to The X-files' cast and crew. Set off the main drag, the studio lot is made up of a handful of gargantuan, grey and white sound stages the size of aircraft hangers. Today it's minus 10 and the air is best described as bracing. A gunmetal grey trailer home, parked just to the left of the main X-Files set, is Gillian Anderson's sparsely furnished, functional home-from-home. Inside, Cleo, a large, black, slavering hound of undetermined breed is throwing toys from one end of the trailer. And she's farting. "Oh Cleo!" says Gillian. And then to me, "It's the food we're giving her." Through the glass-panelled door we can see extras garbed as SWAT team members milling around, their breath turning into instant mist. Gillian plonks herself down on the sofa, dressed in her drab regulation FBI suit, cross legged, munching on a banana.

Face to face the first thing you notice about Gillian Anderson is that she's smaller and prettier than she photographs - she's classy looking and beautiful in a Fifties movie-star kind of way. She stands maybe five-foot three and is spectrally thin. It's no secret that as an FBI agent in The X-files her sexuality is purposely downplayed, her curvy figure hidden in drab suits and big coats. For someone whose star is rapidly on the ascent, she's endearingly bullshit free, displaying not an ounce of Hollywood head-swelling or big-star hauteur. She's fun, approachable and easy to warm to. She seems genuinely flattered when I ask her what it feels like to be a fantasy woman for men around the world.

"The first time I heard it, I was surprised," she admits, leaning over and dumping her banana skin in the bin behind me. "Because I'm not sure how people get the sex symbol thing from Scully. But somebody can be very sexy and not be attractive to look at. There's an aura they have."

Do you like the way you look?

"I'm comfortable with my looks," she muses. "I've had to live with them for 27 years. I've been called 'an unconventional beauty' which is a strange kind of compliment, but I know I'm not a marketable beauty in TV terms. I'm attractive in a different kind of way."

You've become the Anti-Pammy

"I guess so," she laughs. "I've been called 'thinking man's crumpet', which is hysterical. But it's better than being called a bimbo like Pamela Anderson who is only famous for her body - if it is her body. I'd prefer to be known for something a little more worthwhile.

"When Gillian originally auditioned for the role of Scully, she had no idea what to expect and turned up at the producer's office looking scruffy, her hair half way down her back. It was only later that she discovered they were originally looking for a "leggy, blonde, model type" and had to go out on a limb to persuade the studio to give her the role. When she married production designer Clyde Klotz and got pregnant six months into the first series, the producers though of bringing in a new female lead, but decided the Mulder/Scully chemistry was too good to throw away. Hence the unflattering big coats of the last series.

There's a knock at the trailer door. A production assistant tells her she's needed back on the set. "Come on," she says grabbing her overcoat. "Let's see what they want.

"It's just after lunch and we're playing make-believe (it's interesting to note that she took her place in the food queue outside the catering van behind extras, technicians and assistants without fuss). The sun warms our backs as we sit on a picnic bench outside her trailer. Ostensibly we should be talking about the incredible burgeoning success of The X-files, with series three due to start its 24-week run on Sky One on March 5, but getting her to talk about the show isn't proving easy. She eats, drinks, sleeps, breaths X-files up to 16 hours a day, five days a week. So we're playing make-believe: pretending for the sake of conversation that we're in a bar. "Our eyes meet," I say. "I smile. You smile back. It's looking good. What happens next?"

"I probably wouldn't do anything," she says. "I might make eye contact with somebody, but I would expect the other person to make all the moves."

"And if I were to chat you up?"

"Do it without me knowing you were doing it."

"And how should I treat you?" "Be completely selfless. Be un-egotistical, un-egocentric and also not like 'on me' all the time, if you know what I mean? And just let the conversation go where it needs to go. And, umm, ignore me, ha ha! No, don't ignore me, but be your own person and not come up to the bar just because I'm sitting there."

If I said you had a beautiful body would you hold it against me? "That's certainly not the way - and if you tried that I'd probably throw a drink over you." What about bedroom tactics - do you like being bossed around or does the Scully in you take over? "Both. Initially I like the battle play. I like switching back and forth between being in control and being submissive. It's fun that way, that kind of role-playing, because you never know what to expect. It's more exciting.

"Are you adventurous?"

"Uh huh." And as my imagination goes into overdrive picturing exactly what'adventurous' could possibly mean, I decide I need clarification. I mean, Gillian, do you, er, 'break the law' as Paula Yates so memorable put it recently.

"Yes," she says without a moment's hesitation. And then she bursts into fits of laughter: "Ha ha! Yeah. Umm, how did we get into this conversation, ha ha?"

On set. Shooting is in progress. The Pusher, as this episode is called, concerns a brain cancer patient who discovers his tumour has unlocked the latent areas of his mind, lending him heightened extra-sensory powers. In today's big scene, he forces Mulder and Scully to play Russian roulette. The director motions for action and Scully explodes. "You bastard! Damn you! Damn you!" she screams, diving out of the way of a gun shot. The scene calls for Gillian to run full pelt at a wall, wearing a bullet-proof vest. She is called upon to do it time and time again as camera angles and lighting are adjusted. She does this without complaint. Filming The X-files is no picnic; the days are long and conditions are on the Spartan side. Consequently there's no room for inflated Hollywood egos, tantrums, mollycoddling or star hand-holding. Everybody involved with The X-files loves the show. Still, it doesn't look that much like fun.

"It can be," she says unconvincingly, after a suitable pause, back at the trailer. It's getting late and the strain is starting to tell. We find out later that shooting continues till after 2.30am. "It can be fun," she says, "but not always. It's pretty gruelling most of the time, actually." Being cocooned away in Vancouver for most of the year mean that the stars of The X-files live in a bubble and have little idea of the show's popularity. When talk turns to Gillian's 'real-life' she raises an eyebrow. "What life?"

From Gillian Anderson's personal file. Born: Chicago, 1968. Father: Edward. Mother: Rosemary. Raised in Puerto Rico, England (from two till 11) and the American Midwest. Went to school in Grand Rapids, Michigan. Schoolmates thought she had a funny accent and bullied her. An old child until she was 13, she remembers being "withdrawn" and "unpopular at school. I was always off in my own little world or being sent to the principal's office for talking back." Her parents had two further children in quick succession (a boy and a girl) which, she says, only served to further her sense of alienation. She shaved her head, got a three-foot purple mohican, a nose ring and wore $2 dresses. She hints darkly at times of loneliness and despair, of identifying with Jane Horrocks' character in Life is Sweet, and mentions "hurting myself in different ways."

When she was 13 she lost her virginity to "a punk guy who has since become a Neo-Nazi. It was awkward, stupid, unadulterated crap."

I think you'll find that most people's first times are less than mind-blowing. "Yeah, I can't imagine saying at 13 that it was incredibly romantic and that the best lay I've ever had was at 13. No, that's not the case."

When she was 14, she went the whole hog and shacked up with a penniless punk muso, ten years to her senior. They used to sleep rough "in warehouses with no heating and on friends' apartment floors," she remembers. "I guess I felt comfortable in that relationship because I felt dirty and grungy and angry. I used to not like myself," she says matter-of-factly. "I spent time overweight, underweight, wearing black, hiding. But in the past couple of years I've started to open up. What's scary is that I'm doing it in front of millions of people."

Were you promiscuous as a teenager?

"I was, yes. During college I was somewhat promiscuous. Not in a bad way. But it wasn't fun. I like the real stuff, I love the romance of the first courting period, all that kind of stuff appeals to me.

"So why did you do it?

"I think I felt that if somebody liked me, then I was supposed to. I didn't realise I had a choice in the matter. If they liked me, even if they were a complete asshole, I thought that I had to sleep with them! It was another way of getting attention. I think that people really didn't find me attractive - or I never really felt attractive - or I never really felt attractive for years and it was only when I started to shave my head and dressed differently that I realised I had a voice as to who I was and what I stood for, and that made me feel attractive and made people attracted to me. I always dressed in black and in combat boots and had hair that stood up six feet, but still guys were attracted to me and so it was like, "Oh, okay, sure, why not?"

Presumably you were having a good time then. "No, actually, I wasn't. I didn't really enjoy it. I'm not sure that I've ever enjoyed it, ha ha ha," she laughs loud but not long. "No, I'm joking. But I don't think I enjoyed it back then at all. When did I start enjoying sex? Umm ... For a long time I felt it was something I had to do, and it wasn't really a place where I could be free and experiment and enjoy. It was something that one did, you know. So I think it wasn't until I was about 22 that I started to realise that, "Hey, I can enjoy this.' Yeah ..."

The week before her 21st birthday, she gave up drinking. "I loved alcohol," she says. "I actually like alcohol a bit too much. I gave up because it was becoming ... it was just getting too much," she falters. "I just realised that all I wanted to do was drink."

Were you a good drunk or a bad drunk.

"I was very introverted. It would've been fine after the first three drinks if everybody just left. But also it was a sexual stimulant for me. It made me feel much stronger and more confident and sexier and I relied on that for a while."

How much were you drinking.

"Too much. But that's another story and I don't want to talk about it."

Her road-to-Damascus moment came at college when she made a startling discovery. She could act. "My outlook changed, my grades went up and I was voted 'most improved student'," she recalls. Later, graduating with a Bachelor of Fine Arts degree from Chicago's DuPaul University, she moved to New York and "did theatre". After moving to LA on the urging of a friend, she spent a year auditioning, doing the odd bit-part in a soap or TV ad and generally getting nowhere fast. She was about to jack it all in and move back east when she heard about The X-files casting call. She got the part the day her last dole cheque arrived.

Today she says she feels comfortable with herself, and generally considers herself a "positive person. I have to be. I still sometimes have silent freakouts," she says. "But I'm not as hard on myself as I used to be."And then the intercom crackles into life, summoning her back on set to play Russian roulette again. She tells me that the TV standards people are having trouble with the scene they're filming. Apparently it's against TV guidelines to point a gun at someone if only one round is chambered. Six bullets is fine, mind you, but one is a no-no.

"This is very un-Scully." It's two days later in a bright, secluded Hollywood photo studio. Gillian has flown down to audition for a major film role and to be shot for the FHM cover. Right now, wearing little more than an indecently low-cut black lace number, she looks every inch the movie star she's about to become in real life. She wanders past, muttering something about having "a big butt". Nothing, let me assure you, could be further from the truth. She looks trim and in shape. Her make-up is natural and low key, her hair tousled, free of the straight-jacket Scully bob. She looks fantastic.

She says she wants to do a film during the early summer hiatus from shooting The X-files. A role in action adventure with Morgan Freeman is mooted, and also, bizarrely, someone has asked her to appear in an unlikely flick about, ahem, a giant snake. For her part, Gillian would be happy playing a bit-part in a big movie - just to test the water. She's yet to make the break from small-screen TV success to big-screen movie stardom, and is nervous about her chances. But it won't be too long now. Stardom beckons. The X-files is only scheduled to run for another couple of series. "I just hope it's allowed to end when it needs to, and it's not pushed beyond its expectations," she says while the make-up and styling people fuss around her. "I'd be happy for it to go on as long as it needs to go. But I'm sure the sixth and seventh years would be gruelling - if it ever goes on that long."

Someone jokingly mentions that the first shot we should do is Gillian handcuffed to a bed. "Great," she says to gob-smacked looks all round, "where do we start?" She picks out some classy black lingerie that she likes, jokes that her Caesarean section scar is "too low down for you guys to see today" and climbs the stairs into the studio room. The bed setup is first. She lounges on the covers, "like I just rolled out of bed," she says, poking fun at the fact that it's taken two hours to create this "totally natural" effect. She wants her hair up for the next shots, and while it's teased into shape, takes a peek at an Internet page showing her high school pictures. "Some of this stuff is so embarrassing," she moans as an ex-boyfriend's poetry comes up next to a picture of her at 16.

For someone who spends most of her time in straight-laced suits and heavy overcoats in the pissing Vancouver rain, the opportunity to play the vixen in the LA sunshine is a chance not to be missed.

Having seen the work-in-progress Polaroids, she's keen to carry on, fitting in as many last-minute poses before being virtually dragged into a waiting limo. She grabs a pair of handcuffs and asks if anyone has a gun she can use. Somebody nervously mentions that no-one is going to believe this is Scully. Gillian throws them a sideways glance. "Good. That's the point."